Top drawing roll assembly for spinning machines



May 31, 1960 A. SCHILTKNECHT TOP DRAWING ROLL ASSEMBLY FOR SPINNING MACHINES Filed Aug. 12, 1957 INVENTOR. 140 OLF SCH/LTKNECHT.

TOP DRAWING ROLL ASSEMBLY FOR SPINNING MACHINES Adolf Schiltknecht, Winterthur, Switzerland, assignor to Job. Jacob Rieter 8: Co. Ltd., Winterthur, Switzerland, a corporation of Switzerland Filed Aug. 12, 1957, Ser. No. 677,581

Claims priority, application Switzerland Aug. 22, 1956 Claims. (Cl. 19-142) The present invention relates to a top drawing roll assembly for spinning machines.

It is know nto secure the position of the bearing unit in the carrier of the covering of a top drawing roll by means of spring rings or by making use of the elasticity of the carrier. The latter method, however, is unsatisfactory, particularly when the roll is short so that the use of a spring ring is preferred.

When using a spring ring for securing the bearing unit in-the carrier for the roll covering two systems are conventional. In one system the hold is exclusively produced by friction, in the other system the spring ring snaps into a groove which conforms with the ring.

The first system mentioned abo"e is not reliable because the frictional engagement does not completely resist axial forces.

The second system is also not satisfactory, particularly if used with short carriers or sleeves and/or with relatively long bearings. There is not enough room available for effecting a good seal. It also necessitates sleevs of greater wall thickness to provide room for the groove in which the ring is received. It may be necessary to provide a second sleeve which is axially displaceable. All this increases the cost, complicates assembling, and impairs the sealing efiect.

It has been found that pushing of the carrier for the roll covering onto the bearing unit cannot be done quickly and effortlessly without special tools, if spring rings are employed which snap into a groove. The diameter of these rings must be greater than the bore of the carrier in order to produce the desired holding effect and to snap into the groove provided in the carrier. There is a possibility that the spring ring abuts aginst the face of the carrier or jams in the bore when the device is assembled. The difliculties experienced with the conventional snap or spring ring systems are a very serious disadvantage because quick diassembly and assembly of the top roll units for cleaning, lubricating and grinding of the covering is of utmost importance in spinning mills.

It is an object of the present invention to provide a top roll assembly which avoids the difiiculties experienced with conventional structures, which can be quickly and without effort taken apart and assembled, which provides reliable interlocking of the individual parts and which is inexpensive. The assembly according to the invention includes a loosely fitted spring ring for axially securing the bearing in the carrier for the covering of the top roll. The eccentricity of the spring ring is not greater than the difference between the radii of the entry portion of the bore in the carrier and of the periphery of the spring ring, because there is an appropriate clearance between the ring and its carrier. The ring sits loosely on the axle of the top roll and automatically centers the carrier when the carrier is pushed onto the bearing. An important feature of the assembly according to the inven tion is that the spring ring axially and permanently presses the bearing against an abutment in the carrier when the device is assembled and in normal operating condition.

nited States Patent 0 2,938,242 Patented May 31, 1960 ice Fig. 2 illustrates a centering ring used in the device shown in Fig. l. 1

Fig. 3 is an axial section of the device with the parts in position during insertion of the bearing unit.

Like parts are designated by like numerals in all figures .of the drawing.

A carrier 1 for the covering of the top roll is provided with a bore 3 for receiving the journal bearing assembly 2. The bore 3 snuggly fits the bearing. A bore 4 of somewhat greater diameter is provided coaxially of the bore 3 and between the latter and the inlet opening of the bores. An axle 6 extends from the hearing unit 2 to the outside and carries an annular sealing ring 5 of U-shaped cross sectional configuration. The bearing unit includes a screw whose head 7 projects from the left side of the unit as seen in the drawing. The screw head 7 extends into a bore 8 which is of smaller diameter than the bore 3 and placed axially thereof. In this way a shoulder 9 is formed which serves as an axial abutment for the bearing unit 2. A spring ring 10 whose outer periphery is circular is loosely supported by the axle 6 and placed between the sealing ring 5 and the hearing 2. The ring 10 is split at 11, as shown in Fig. 2, so that it can be deformed in the radial direction. At the entry side of the bore 4 a conical entry portion 13 is provided whose small diameter is adjacent to the bore portion 4 and is the same as that of the bore 4 and whose great diameter is somewhat greater than the outside diameter of the untensioned spring ring 10. Between the bore portion 4 and the bore portion 3 an annular recess 12 is provided which has a conical cross section similar to that of the entry portion 13, the small diameter {art of the recess being adjacent to the bore portion 4 and having the same diameter. The axle 6 is provided with a collar 14 between the sealing ring 5 and the bearing 2.

The split spring ring 10 is provided With at least three internal protuberances 15 having surfaces facing the axle 6 and being arranged on a circle whose diameter is somewhat greater than the diameter of the shaft 6, when the ring is untensioned. When the ring is pushed into the bore 4 it is radially compressed and the inner surfaces of the protuberances 15 are close to the periphery of the collar 14 and center the spring ring.

Fig. 3 clearly shows a clearance between the bearing 2 and the bore portion 4. This facilitates insertion and removal of the bearing into and from the carrier member 1. Frictional forces must be overcome only when the bearing is moved to its final position in the bore portion 3.

When moving the bearing unit into the bore in the carrier 1 the spring ring 10 easily slips into the conical entry portion 13 of the bore and does not abut against the right face of the element 1 because of the relationship between the length of the diameters of the entry portion 13, of the outside periphery of the ring 10, of the collar 14, and of the inner surfaces of the spring ring 10 facing the collar 14. The spring ring 10 facilitates centering of the bearing unit 2 in the bore of the element 1 shortly after insertion and passage of the spring ring through the entry portion 13. When the bearing unit 2 has almost reached its final position the spring ring 10 snaps into the recess 12 and partly expands so that is, therefore, always pressed to the left against the abutment 9 by the action of the resilient ring 10.

The bore 4 serves two purposes, firstly it is a centering aid during insertion of the bearing into the carrier member 1 and secondly, in cooperation with the sealing ring 5 whose outside diameter is somewhat smaller than the diameter of the bore portion 4, it prevents entry of fly, etc., into thebore of the member 1.

1 claim:

1. A top drawing roll assembly for spinning machines including a bearing unit, a roll covering carrier, a bore in said carrier for coaxially receiving said bearing unit, said bore having a conical entry portion whose opening is greater than that of the bearing unit, an axle coaxiaily extending from said bearing unit and through saidentry portion when the bearing unit is in operating position, and a split spring ring carried coaxially of said bearing unit by said axle when said ring is compressed and loosely resting on said axle in eccentric position when said ring is expanded, the difierence between the radii of the opening of said conical entry portion and the periphery of the expanded ring not exceeding the eccentricity of the losel'y carried ring.

2. A top drawing roll assembly as defined in claim 1, said bore having an interior portion snuggly' fitting said amazesbearing unit and a cylindrical intermediate portion be tween said interior portion and said entry portion, the diameter of said intermediate portion being smaller than that of said entry portion and greater than that of said interior portion.

3. A top drawing r011 assembly according to claim 2 in which said entry portion is conical, the small diameter of the entry portion being adjacent to said intermediate portion and equal to the diameter of said intermediate portion an. annular recess of substantially conical cross section being interposed between said intermediate portion and said interior portion, the small diameter of said recess being adjacent to said intermediateportion and being equal to the diameter of said intermediate portion.

A top drawing roll assembly according to claim 3, the outside idameter ofithe untensioned spring ring being greater than the diameter of said intermediate portion, said ring having at least three internal protuberances abutting against said axle when said ring is pushed into said intermediate portion and compressed.

5 A top drawing roll assembly according to claim 3, said interior portion having an axial abutment against which said bearing unit is pressed by the action of said spring ring in said annular recess of substantially conical cross section.

FOREIGN PATENTS- 1 049,57l France Aug. 19, 1953 

